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41.
以40个不同基因型万寿菊(Tagetes erecta)叶片为外植体, 在相同条件下诱导不定芽分化, 获得最佳再生基因型; 然后分析不同激素组合、外植体切口方式、固化剂及蔗糖对万寿菊再生和玻璃化影响; 最后对不同类型的伸长培养基进行探索。结果表明, 最佳再生基因型为里程碑·黄色; 最佳再生培养基为MS+0.2 mg·L?1 TDZ+0.5 mg·L?1 IBA+8 g·L?1琼脂+40 g·L?1蔗糖, 再生率达70%, 玻璃化率降低至16%; 最适再生的小叶部位为全小叶; 最适伸长培养基为MS+8 g·L?1琼脂+30 g·L?1蔗糖, 伸长率达91.3%。该研究建立了高效稳定的万寿菊再生体系, 解决了万寿菊再生过程中严重的玻璃化问题, 可为万寿菊的遗传改良和基因功能研究奠定基础。  相似文献   
42.
Allergic inflammation and severe allergic reactions (anaphylaxis) are important in allergen induced diseases. Bacterial products such as lipopolysaccharide (LPS) are ubiquitous and can facilitate allergen induced Th2 immune responses. Phosphatase SHP-1 is critical in regulating immunological homeostasis and in allergen induced Th2 immune responses in the lung. However, the mechanisms underlying the initiation of allergic inflammation and allergen induced anaphylaxis are still not completely elucidated and it is unclear whether SHP-1 plays any role in LPS-induced airway inflammation and in allergen-induced anaphylaxis. In this study we tested the hypothesis that phosphatase SHP-1 plays an important role in allergic inflammation and anaphylaxis and determined whether its effects are through regulation of mast cell functions. SHP-1 deficient (mev/+ and mev/mev) and mast cell deficient (KitW-sh) mice were examined in their responses to LPS airway stimulation and to ovalbumin (OVA) allergen induced systemic anaphylaxis. Compared to wild type mice, mev/+ mice had significantly enhanced LPS induced airway inflammation and OVA induced anaphylactic responses, including hypothermia and clinical symptoms. These changes were mast cell dependent as KitW-sh mice had reduced responses whereas adoptive transfer of mast cells restored the responses. However, T and B cells were not involved and macrophages did not play a significant role in LPS induced airway inflammation. Interestingly, basophil differentiation from SHP-1 deficient bone marrow cells was significantly reduced. These findings provided evidence that through regulation of mast cell functions SHP-1 plays a critical role as a negative regulator in allergic inflammation and in allergen induced anaphylaxis. In addition, SHP-1 seems to be required for normal basophil development.  相似文献   
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模拟氮沉降对华西雨屏区苦竹林凋落物基质质量的影响   总被引:2,自引:0,他引:2  
凋凋落物基质质量是影响凋落物分解速率的决定性因子之一,本研究旨在探究模拟氮沉降对苦竹林凋落物基质质量的影响。2007年11月至2010年12月每月一次连续对华西雨屏区苦竹人工林进行了模拟氮沉降试验,施氮水平分别为:低氮(5 g N?m–2?a–1),中氮(15 g N?m–2?a–1)和高氮(30 g N?m–2?a–1)。在施氮2 a后,于2010年1月开始收集各样方的凋落物样品,连续收集12个月,分析测定凋落物基质质量。结果表明:施氮显著增加了凋落叶中N、P元素含量,中氮处理显著增加了凋落枝中N元素含量,中氮和高氮处理均显著增加了凋落枝中P元素含量;施氮对凋落物中C元素含量影响很微弱,显著降低了凋落叶中的C/N,中氮处理显著降低了凋落枝中的C/N,对木质素和纤维素含量均未造成显著影响。由于模拟氮沉降增加了苦竹凋落物的N、P含量,降低了其C/N,因此氮沉降可能会促进苦竹凋落物的初期分解速率。  相似文献   
45.
The molecules encoded by major histocompatibility complex (MHC) genes play an essential role in the adaptive immune response among vertebrates. We investigated the molecular evolution of MHC class I genes in the sable Martes zibellina. We isolated 26 MHC class I sequences, including 12 putatively functional sequences and 14 pseudogene sequences, from 24 individuals from two geographic areas of northeast China. The number of putatively functional sequences found in a single individual ranged from one to five, which might be at least 1–3 loci. We found that both balancing selection and recombination contribute to evolution of MHC class I genes in M. zibellina. In addition, we identified a candidate nonclassical MHC class I lineage in Carnivora, which may have preceded the divergence (about 5257 Mya) of Caniformia and Feliformia. This may contribute to further understanding of the origin and evolution of nonclassical MHC class I genes. Our study provides important immune information of MHC for M. zibellina, as well as other carnivores.  相似文献   
46.
Evolution of the IL17 receptor family in chordates: a new subfamily IL17REL   总被引:1,自引:0,他引:1  
Wu B  Jin M  Zhang Y  Wei T  Bai Z 《Immunogenetics》2011,63(12):835-845
The human interleukin 17 receptor (IL17R) family plays a critical role in inflammatory responses and contributes to the pathology of many autoimmune diseases. So far, five members, IL17RA to IL17RE, have been identified. Recently, some IL17R genes have been identified in non-mammalian species, such as zebrafish IL17RD; however, there are no reports on the evolutionary history of this complex gene family through comparative phylogenetic approaches. Here, we concentrated on the IL17R evolution in chordates. There are two IL17Rs in the genome of the basal chordate amphioxus: IL17RA and IL17RD. After two rounds of whole genome duplications, these two IL17R genes expanded into five early vertebrate IL17R genes, IL17RA to IL17RE. IL17RA and IL17RD are found in most vertebrates, whereas the other three, IL17RB, ILR17RC, and IL17RE, underwent some loss in vertebrates during evolution. Our sequence and structure analyses reveal functional similarities and distinctions between the different IL17Rs. Based on similarity searches for IL17R-like proteins within chordate sequences, a group of IL17RE-like (IL17REL) proteins were identified from mammalians to lower vertebrates. In silico and expression analyses on the novel IL17RELs showed that this group of receptors is highly conserved across species, indicating that IL17REL may represent a unique subfamily of IL17Rs.  相似文献   
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Neuropathic pain is a somatosensory disorder which is caused by disease or nerve injury that affects the nervous system. microRNAs (miRNAs) are proved to play crucial roles in the development of neuropathic pain. However, the role of miR-202 in neuropathic pain is still unknown. Sprague-Dawley rats were used for constructing the neuropathic pain model. The expression of miR-202 was determined by quantitative real-time polymerase chain reaction. Potential target gene for miR-202 was measured using bioinformatics methods and Western blot analysis. In this study, we used rats to establish a neuropathic pain model and measured the effect of miR-202 in neuropathic pain. We demonstrated that miR-202 expression was downregulated in the spinal dorsal horn of bilateral sciatic nerve chronic constriction injury (bCCI) rat. However, miR-202 expression was not changed in the dorsal root ganglion, hippocampus, and anterior cingulated cortex of bCCI rat. We identified that RAP1A was a direct target gene of miR-202 in the PC12 cell. RAP1A expression was upregulated in the spinal dorsal horn of bCCI rat. Overexpression of miR-202 could improve the pain threshold for bCCI rats in both hindpaws, indicating that miR-202 overexpression could lighten the pain threshold for model rats. Moreover, RAP1A overexpression increased the pain threshold effect of miR-202 overexpression treated bCCI rats, indicating that miR-202 could lighten the pain threshold through inhibiting RAP1A expression. These data suggested that miR-202 acted pivotal roles in the development of neuropathic pain partly through targeting RAP1A gene.  相似文献   
49.
Liu  Baojun  Zhou  Ying  Lan  Wu  Zhou  Qin  Li  Fei  Chen  Feng  Bao  Manzhu  Liu  Guofeng 《Plant Cell, Tissue and Organ Culture》2019,136(3):489-498
Plant Cell, Tissue and Organ Culture (PCTOC) - Suspension-cultured Dracocephlum polychaetum Bornm. is a wild medicinal herb native to Iran, treated with a static magnetic field (SMF) and Fe2O3...  相似文献   
50.
以金黄花滇百合(Lilium bakerianum var. aureum)的鳞片为外植体, 探讨不同部位外植体和不同配比的植物生长调节剂对愈伤组织诱导和植株再生的影响。研究结果表明, 鳞片诱导愈伤组织和不定芽的最适培养基为MS+1.0 mg∙L -16-BA+0.1 mg∙L -1NAA+30 g∙L -1蔗糖; 不定芽增殖的最适培养基为MS+0.5 mg∙L -16-BA+0.1 mg∙L -1NAA+30 g∙L -1蔗糖; 不定芽诱导小鳞茎的最适培养基为MS+1.0 mg∙L -1NAA+30 g∙L -1蔗糖; 小鳞茎膨大生根的最适培养基为1/2MS+0.01 mg∙L -1NAA+60 g∙L -1蔗糖。该研究为金黄花滇百合种质资源保护和快速繁殖提供了技术支撑。  相似文献   
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